A resurgence in Guinness sales has put drinks giant Diageo back on track, giving a boost to its share price as investors raised their glasses to the interim results.

The company has credited a major advertising push in late 2007 for increasing Guiness sales by 6% during the second half of the year. This is despite a declining beer market.

Its other brands also fared well, with double digital sales growth seen by Johnnie Walker whisky, Smirnoff vodka and Captain Morgan rum.

Diageo's group operating profit increased by 9% during the trading period. Pre-tax profit was up 5% to £1.37 billion, in line with analyst forecasts.

Chief executive Paul Walsh said: 'While we continue to watch for any impact that recent financial market volatility may have on broader trading conditions, we are maintaining our guidance for the current year.'

The company is pushing key brands in other fast-growing markets such as Eastern Europe and Russia, offsetting weaker sales in Spain and Greece. Across Europe, operating profits rose 2% to £509 million.

In the US, a weaker dollar against the pound hit the business although underlying operating profits were 7% higher at £491 million after raising the prices of its spirits.

Diageo believes its broad geographical spread offer some protection from economic slowdown. Scotch sales are doing well in Latin America and the Middle East and the group is moving into new Asian markets including Vietnam. However, the company lost its import licence in Korea last summer, which dampened growth for the Asia Pacific region.

To mitigate weaker beer markets in the UK, Diageo is increasing its exposure to the 'super-premium' market. Last week it secured a 50% stake in Dutch vodka brand, Ketel One. It has increased advertising on 'super premium' brands within the Jose Cuervo tequila stable, including Black Medallion and Platino.

Stockbroker Blue Oar said Diageo's half-year results were 'satisfactory, but not knock-out figures.' It said there was little indication of how the US consumer is responding to economic turbulence. 'The premiumisation policy is still holding up, the growth is being driven in international markets and the key brands (Smirnoff and Johnnie Walker) show no signs of losing their glitz,' said analyst Bruce Davidson.

Shares in Diageo were up 3.5% to £10.69 in early trading on Thursday.